Hi, Gents:
From the Lyman Cast Bullet Handbook, page 50.
"In most antimonial alloys, arsenic ranges from 0.05 to 0.5%; the typical concentration in wheel weights is about 0.17%. At these concentrations, the arsenic is no more a toxic hazard than the antimony and its presence permits wheel weights and other such alloys to be heat treated to 30BHN or more."
As I understand it, arsenic is more toxic than antimony, but at the low concentrations in bullet metal compared to the 3-11% level of antimony in typical alloys, it isn't a problem. That is, if you have adequate ventilation for the other fumes. If you smell garlic, or taste it in the back of your mouth, get some fresh air, fast. Note that only one of the listed babbitts is over 0.6% antimony, at 1.4%.
Bye
Jack